Apparatus for use in treating cellulose compositions with solvent vapors



K. C. UNDERWOOD, J. E. CRANE, AND J. M. KESSLER.

APPLICATION FILED MAY 2, 1919.

Patented Apr. 11, 1922.

APPARATUS FOR USE IN TREATING CELLULOSE COMPOSITIONS WITH SOLVENTVAPORS.

TATQJYGQ.

Newark, in the county of Essex and State" entree stares rarer eerie,

KENNETH C. UNDERWOOD, OF NEWARK. NEW JERSEY, JASPER E. CRANE, OF WIL-MINGTON, DELAWARE, AND JOHANNES M. KESSLER, OF WEST ORANGE, NEW

J'EY, ASSIGNORS T E. I. DU FONT DE NEMOUBS & COMPANY, OF WILMINGTON,DELAWARE, A GQBQRATION OF DELAWARE.

Area Remus non. USE IN TREATING ennaunosn ooiurosrrxous WITH SOLVENTvarons.

I Specification of Letters Patent. Patented Apt. llll, 11%? Applicationfiled May Q, 1919. SeriaI No. 294,826.

To all whom it may concern:

Be it known that we, KENNETH C. UNDER- woon, a citizen of the UnitedStates, of

"-ofNew Jersey JAsrnn E. CRANE,a citizen of the United States, ofWilmington, in the county of New Castle and State of Delaware, andJOHANNES M. Knssnnn, a citizenof Germany, of West Orange, in the countyofEssex and State of New Jersey,

1 vented a certain new and useful Improvement in Apparatus for Use inTreating Cellulose Compositions with Solvent Vapors,

and do hereby-declare that the following" is a full, clear, and-exactdescription thereof.

Our invention relates particularly to an apparatus by ,rneans of whichcellulose compositions may be treated with solvent vapors for thepurpose of providing smooth surfaces for the same. i

The object of our invention is to provide an apparatus by means of whichcellulose compositions, and particularly compositions which have beenmade from cellulose plastics, such for example as pyralin or celluloid,may be treated with solvent vapors, as for example, vapors of methylalcohol, so that the surfaces thereof will be sufliciently softened inthis manner to enable them to be provided with smooth surfaces, by theapplication of pressure from a highly polished plate. In the manufactureof sheets of cellulose compositions, as for example, pyralin orcelluloid, it is customary to out said sheets from a pressed block ofsaid material. The cutting of these sheets, however, leaves certainknife marks which it is necessary to remove, as

otherwise there would remain upon the sheets ridges rendering thesurfaces thereof rough and .semi-opaque when made from transparentmaterials. It is the object of our invention especially to provide aconvenient, effective and economical apparatus means of which theseknife marks and the surfaces of similar unevennesses in these sheets maybe removed. A further object is to treat the sheets of material at aconstant and greater velocity and more uniformly than is to avoid thedetrimental effects due to have -in= formerly. Another objectv thepresence of moisture, which if present produces white spots owing totheprecipitation of pyroxylin-in the pyralin or celluloid;

workmenbecause of vapors escaping into the atmosphere.

. lint-general,- our invention comprises an apparatus 'which'is designedtov apply to such sheets of material a current of heated solventvapors,such for example as methyl alcohol vapors, so as to superficially softenthe surfaces of the same, while at the same time effectively recoveringunused vapors supplied, to the apparatus, vapors which are adjacent tothe treated surfaces, but which have not entered the same. Furtherobjects of our invention will appear from the detailed descriptionthereof contained hereinafter.

While our invention is capable of embodiment in many different forms,for the purpose of illustration we have shown only one form of ourinvention in the accompanying drawings, in which;

Fig. 1 is a' rear elevation of an apparatus made in accordance with ourinvention, and

Fig. 2 is a vertical section through a portion of the same.

In the drawings, we have shown a plurality of uprights 1, having aplatform 2 thereon, supporting an alcohol vaporizer 3, which is shown asprovided with a steam inlet pipe a, a steam outlet pipe 4, and analcohol level gage 5. Said vaporizer is preferably connected'by means ofa pipe 6 to a narrow vapor applying chamber? having a steam jacket 8surrounding the same, which'is shown as provided with a steam pipe 9.Said vapor applying chamber 7 preferably has entering the same an inletopening 11 and an outlet opening 12, which are provided with lower andupper guide plates 13 and 14. having perforations 15 and 16 respectivelyto permit the passage through the same of the methyl alcohol vapors. Theguide plates 13 and 14 are designed to guide sheets of a nitrocellulosecomposition, such for example as pyralin or celluloid 17, which arepreferably forced through the same by means of a pair of heated rollers18 and 19 including the 1 heated with a current of steam supplied bymeans of inlet and outlet pipe 20 and 20 the interiors of said rollersbeing shown as connected by means of a pipe 21 through, swing joints orglands 20 located at the other end thereof. In advance of the rollers 18and 19 there are shown two additional guide plates 21* and 21 to guidethe sheets 17. The rollers 18 and 19 are shown as drivenby a gear'22meshing with a pair of gears 23 and 24 on the rollers 19 and 18respectively. The gear 22 preferably has attached thereto a sprocket 25carrying a chain 26 which, in the embodiment shown,

passes over a sprocket 27 on a shaft 28, which shaft 28 carries a pulley29, driven by a belt 30 from a motor shaft'31, carrying anotherpulley32. Adjacent to the lower and upper outlet opening guide plates 13 and14, there are shown two suction boxes 33 and 33 having perforations'34-communieating with the opening'l2, said boxes beingshown as connected bya pipe 35 to the suction side of a suction pump 36, driven by a pulley37 and a belt 38from a pulley 39 on the motor shaft 31; The vapors whichare thus drawn into the pump 36 may pass out by a vapor pipe 41 to acoil condenser 42-supplied with an agent such as cooling water by meanssuch as pipes -13 and 44.

The condensed methyl alcohol preferably passes out from the condenser bya pipe 45, and any uncoudenscd vapors may escape by a pipe 46 therefrom,to be recovered in any suitable way, if desired.

In the operation of the described embodi ment of our invention, sheetsof pyralin or celluloid 17 are fed between the guideplates 21 and 21 tothe heated rollers 18 and 19,

These rollers are heated to prevent condensa- I tion of alcoholvapor'with consequent softenmg and sticking-of portions of the pyralin.or celluloid "sheets 17 thereto, inasmuch as such condensation,softening and adhesion passes out of theichamber 7, it is broughtwouldoccur 'if 'the rollers were not heated.

They, furthermore, force the sheets through the chamber 7 in, thedesired direction over [the perforations '15 and 16, so that a currentof i the heated methyl "alcohol vapors is brought into contact with theunder and upper surfaces thereof Asjeach sheet 17 1 1' through thesuction boxes 33 and 33, where alcohol is; collected ,the residualmethyl j v I not many suitable manner, asdesired. The

any vapors adjacent the surfaces of the sheets are removed, and areconducted to the suction pump 36, and driven by the same into thecondenser42. The. condensed methyl from the pipe 45, while alcoholvapors are conveyed'away by the pipe46 forfrecovery or surfaces ofthese'sheets having now been softened by v vapors, said sheets aresubjected. to pressure the application of the solvent between polishedmetal plates, so that in this plates containin way all of thesuperficial roughnesses present in the plates as they come from thecutters are removed.

While we have described our invention above in detail, We wish, to beunderstood that" many changes may be made therein a without departingfrom the. spirit thereof.

Claims: '1. An apparatus comprising a solvent Wtpor applying chamber,means for passing a through, and means to recover vapors which do notpass away with the sheet.

por applying chamber, means forpassing a sheet of a nitrocellulosecomposition there- 2. An apparatus comprising'a solvent va-- sheet of anitrocellulose composition therethrough, and means to recover vaporswhich; do not pass away with the sheet, comprising a vapor outlet pipefrom said chamber, and means directly connected therewith to condensesaid vaporsobtained therefrom.

3; An-apparatus comprising a solventvapor-applying chamber, means forpassing 5 'mounted to feed the sheet in between the said plates. y

, 5. An apparatus, comprising a solvent vapor applying chamber, meansfor passing a sheetof material therethrough comprislng perforationspositioned within the cham "er, rollers provided with heatin means, saidrollers beingmounted to feed t e sheet in between the said lates, andplates for guiding the sheetto and from the'rollers.

6. 'An apparatus comprising a vapor applying chamber,1a plate within thechamber having a perforation therein to guide a sheet of anitrocellulose composition while being subjected to said vapors, andheated rollers for feeding said sheet into the chamber, and means torecover solvent 3 vapors comprising a suction device adjacent the pointof exlt'of the sheet from the chamber and'a. condenser connectedthereto.

7. An apparatus comprising a solvent vapor applying chamber, means forpassing a sheet of material therethrough comprising plates containinperforations positioned within the cham er, rollers provided withheating means, said rollers being mounted to feed the sheet in betweenthe said plates,

plates for guiding the sheet to and from the rollers, and means torecover solvent vapors said. sheets to the rollers and from the rollerscomprising a suction device adjacent the to the plate With the opening.point of exit of the sheet from the chamber In testimony that We claimthe foregoing and a condenser connected thereto. We have hereunto setour hands.

8. An apparatus comprising a vapor ap- KENNETH C. UNDERWOOD. plyingchamber, a plate Within the chamber JASPER E. CRANE. having aperforation therein to guide a sheet JOHANNES M. KESSLER. of anitrocellulose composition While being Witness as to Jasper E. Crane:subjected to said vapors, rollers provided P. E. STRICKLAND.

with heating means for feeding said sheet Witness as to J. M. Kessler:into the chamber, and guides for conducting K. UNDERWooD.

